Controlled-jet-supported hovering platform chiefly for use in mine clearing



Dec. 3, 1963 D M 3,112,669

CONTROLLED-JET-SUPPORTED HOVERING PLATFORM CHIEFLY FOR USE IN MINE CLEARING Filed Dec. 11, 1961 FIG:1

Louis Damblcuoc.

WATSON, COL, 61in; 4- Jo-Eon Afibmzey:

United States Patent CONTROLLED-JET-SUPPORTED HOVERING PLAT- FORM CHIEFLY FOR USE IN CLENG Louis Jean Damblanc, Paris, France, assignor to Socicte Nationale dEtude et de Construction de Moteurs dAviation, Paris, France, a company of France Filed Dec. 11, 1961, Scr. No. 158,294 I Claims priority, application France Dec. 14, 1960 6 Claims. (Cl. 891) 1 The explosion of land-mines is generallydue to the .pressure exerted on the ground by a foot-soldier or a Q on the ground a local'pressure of given magnitude that t is unrelated to the weight of the platform, which may be very low. Such a platform may thus be caused to move at high speed through a minefield. A high rate of travel,

which is in itself advantageous inasmuch as it enables the device to sweep a large area in' unit time, automatically provides a secondary benefit in that the platform is rapidly placed out of range of dangerous splinters and blast effects.

A preferred form of this invention comprises a battery of rockets equipped with nozzles which direct towards the ground juxtaposed jets that sweep the strip to be cleared of mines. This battery of rockets is disposed in a general direction oriented transversely relative to the line of travel of the platform. The weight of the platform is very much less than the thrust developed by the rockets with which it is equipped. It is therefore a further object of the invention to provide these rockets with countering nozzles which equilibrate, in part at least, the downwardly directed thrust.

Since rockets are motors possessing very little flexibility, particularly the less expensive solid fuel type, fine adjustment of the resultant thrust is ensured by other rockets whose function is to propel the device and which are slightly inclinable relative to the horizontal.

Since the pressure exerted on the ground is solely the consequence of a jet of particles the reaction from which provides the lift required to support the platform, the said platform may be said to constitute the means whereby a directed jet force is ensured, this force being greater than the resultant of the thrust developed by the reaction motors as a whole, equipped with their countering noz zles. This characteristic may be applied for purposes other than mine clearing, for example in space vehicles.

The description which follows with reference to the accompanying drawing, filed by way of example only and not of limitation, will give a clear understanding of the invention and of the method of carrying it into practice, such particularities as emerge from the description or the drawings naturally falling within the scope of this invention.

Referring to the single drawing filed herewith:

FIGURE 1 is a highly diagrammatic perspective view of a rocket platform according to the invention;

FIGURE 2 is a schematic sectional view of one of the lift rockets;

FIGURE 3 is a schematic view of a propulsive nozzle which is inclinable to permit fine adjustment of the total lift; and

FIGURE 4 is a section through a rocket equipped with I an additional propulsive nozzle.

1 Reference is now had to FIGURE 1, which is a rear three-quarter view of a platform consisting basically of a supporting structure 1 and a battery of vertical rockets 2 and propulsive rockets 3.

The structure 1 comprises pre-utilization supporting means which may be used also for guidance during the launch phase, an example being skis i.v The structure 1 supports the propulsion rockets 3 through the medium of pivots 5, and said rockets are operated by servo-mechanisms 6 controlled by a device 7 (not shown).-

Stabilizing control surfaces, such as fins 8, areaffixed to the structure. i:

The rockets 2 are preferably of the solid fuel type, but

may, for certain applications, utilize a liquid or other conzles 13 will be determined by the effect sought on the ground, and that of the countering upper nozzles 14 by the weight of the device and the thrust exerted by the nozzles 13.

Considering now FIGURE 1, it will be seen that the rockets 2 are mounted in a bank of which the transverse" dimension, as referred to the direction of travel A, is greater than the longitudinal dimension, and said rockets are preferably set up in staggered rows. The diameter of the section of the jet efliux, at the point where the jet impinges on the ground, is generally less than the diameter of the rocket casing.

The propulsive rockets 3, which may utilize solid liquid or any other convenient fuel, pivot about trunnions 5 in response to actuators 6. When they are so pivoted downwardly, their thrust P has a vertical component V which may be varied to compensate for the lightening process as the fuel is consumed.

The propulsive function of the rockets 3 may alternatively be fulfilled by appropriately oriented nozzles in the casings 9 of a number of said rockets 2.

Such a nozzle 15 is illustrated in FIGURE 4.

The platform hereinbefore described is operated in the 'fOHOWiHg manner:

After mounting the platform on a suitable launching ramp for instance on a rail-mounted carriage-and after orienting it in the direction of the minefield'through which a path is to be cleared, the rockets are ignited.

The resultant of the thrust exerted bythe nozzles 13 used for mine clearing amply exceeds the weight of the device, but the countering nozzles 14 produce a thrust which is opposite to said resultant, and this thrust is added to the weight of the device in order to ensure equilibrium at least during the steady state while rocket combustion is under way.

The variable inclination of the propulsive rockets permits fine lift adjust-ment, which may be slaved to the altitude or to the vertical accelerations of the platform.

A platform according to the present invention thus provides a mine clearing device operating at very high speed, it being possible to clear several dozen yards per second. In addition, the platform is easy to transport and to operate, and is relatively inexpensive.

Manife-stly, a vertical disposition of the rockets is by no means mandatory, and it is equally clear that this invent-ion covers any alternative layout of reaction motors than mine clearing, Wherever the object sought or the means envisaged involve recourse to equivalent technical means.

What I claim is:

1. A hovering platform adapted for mine clearing purposes and having a longitudinal axis comprising, in combination, a battery of rockets with countering nozzles all oriented in a substantially vertical direction and disposed in two series, a first series directed toward the ground and transversely ranked with regard to said axis in such manner that the hot gases ejected apply a high pressure onto the ground along at least a continuous line substantially as broad as said first series and a second series directed upward so as to reduce the resulting thrust applied to the platform to a value substantially equal to its weight, propulsive and stabilizing means, whereby the platform hovering at a small height causes the mines to explode within a path crossing a mine field.

2. A hovering platform adapted for mine clearing purposes and having a longitudinal axis comprising, in combination, a battery of substantially vertical rockets equipped each with two coaxial countering nozzles of unequal area and transversely ranked with regard to said axis, a first series of larger area nozzles being directed toward the ground in such manner that the hot gases ejected apply a high pressure onto the ground along at least a continuous line substantially as broad as said first series and a second series of smaller area nozzles being directed upward so as to reduce the resulting thrust applied to the platform to a value substantially equal to its 4 weight, propulsive and stabilizing means, whereby the platform hovering at a small height causes the mines to explode within a path crossing a mine field.

3. A hovering platform as claimed in claim 2 wherein the nozzles directed toward the ground form alternate rows to reinforce the transverse continuity of the hot gas action on the ground.

4. A hovering platform as claimed in claim 2 wherein said propulsive means consists of a reaction motor independent of said rockets.

5. A hovering platform as claimed in claim 4 wherein said reaction motor is mounted on a pivot which is substantially horizontal and perpendicular to the direction of travel of the platform, in order that its oscillation about said pivot should produce an adjustable lift component of thrust.

6. A hovering platform as claimed in claim 2 wherein said propulsive means consists of a nozzle oriented toward the rear of the platform and fed with gas by said rockets.

References Cited in the file of this patent UNITED STATES PATENTS 2,409,848 Gruelich Oct. 22, 1946 2,613,497 MacDonald Oct. 14, 1952 2,771,841 De Fino Nov. 27, 1956 2,850,976 Seifert Sept. 9, 1958 2,947,500 Dreyer et al. Aug. 2, 1960 2,981,501 Schaefer Apr. 25, 1961 3,022,026 Shaw Feb. 20, 1962 

2. A HOVERING PLATFORM ADAPTED FOR MINE CLEARING PURPOSES AND HAVING A LONGITUDINAL AXIS COMPRISING, IN COMBINATION, A BATTERY OF SUBSTANTIALLY VERTICAL ROCKETS EQUIPPED EACH WITH TWO COAXIAL COUNTERING NOZZLES OF UNEQUAL AREA AND TRANSVERSELY RANKED WITH REGARD TO SAID AXIS, A FIRST SERIES OF LARGER AREA NOZZLES BEING DIRECTED TOWARD THE GROUND IN SUCH MANNER THAT THE HOT GASES EJECTED APPLY A HIGH PRESSURE ONTO THE GROUND ALONG AT LEAST A CONTINUOUS LINE SUBSTANTIALLY AS BROAD AS SAID FIRST SERIES AND A SECOND SERIES OF SMALLER AREA NOZZLES BEING DIRECTED UPWARD SO AS TO REDUCE THE RESULTING THRUST APPLIED TO THE PLATFORM TO A VALUE SUBSTANTIALLY EQUAL TO ITS WEIGHT, PROPULSIVE AND STABILIZING MEANS, WHEREBY THE PLATFORM HOVERING AT A SMALL HEIGHT CAUSES THE MINES TO EXPLODE WITHIN A PATH CROSSING A MINE FIELD. 